That which is restrictive

This is quite a long post about a distinction some people make between that and which as relative pronouns — an oft-disputed point of English usage. Feel free to skip ahead if you’re familiar with the territory.

The underlined clause is integral to the sentence, for reasons context would normally make clear. For example, there may be an implication that I have access to other bikes, so the restrictive clause defines or restricts what bike I’m talking about.

Non-restrictive clauses (also non-defining or supplementary relative clauses) are bound less tightly to the sentence: they can be removed without changing its essential point. Thus:

The bike, which I keep in the garage, is ideal for short trips.

Here, there’s only one bike I could be referring to, and the information about where I keep it is supplementary, non-defining, dispensable.

In speech, non-restrictive clauses are intoned separately; in writing, this separation is marked by punctuation: normally commas, as above, sometimes dashes or parentheses.

There’s a good case for calling non-restrictive clauses supplementary relative clauses, and restrictive ones integrated relative clauses. But these terms are quite new, and in this post I use the more familiar names.

So far so uncontroversial. Then there are sentences like this:

The bike which I keep in the garage is ideal for short trips.

And shazam!, opinion is divided. To me, this sentence is essentially equivalent to the first example — the one with that — though if I spoke it I’d probably use that or neither. (What is a non-standard alternative.) But some would call this which ambiguous and improper, saying it should not be used with a restrictive clause.

The issue cropped up in a recent post about whom. A reader objected to restrictive which; I said restrictive that was not a grammatical requirement — it never has been — and I quoted the Chicago Manual of Style (“which can be substituted for that in a restrictive clause”) and other sound authorities in support of this position. See John E. McIntyre for a clear and common-sense summary.

Restrictive which is avoided in AmE more than in BrE. Garner’s Modern American Usage (1998) describes two schools of thought, neither of which I fit into. He says British writers “have utterly bollixed the distinction between restrictive and nonrestrictive relative pronouns”. But it’s not about distinguishing between pronouns: it’s about different types of clause; and commas, used correctly, signal that distinction.

* * *

Yesterday, The Guardian’s Mind your languageblog firmly advocated the that/which pseudo-rule. It began with a reader’s niggle and ended by claiming that the line “All molecules which are drugs bind to receptors” fails to be “clear, unambiguous and factually correct”. But it looks fine to me. I responded with a couple of comments, which I’ll cannibalize here rather than rewrite. First:

I find nothing unclear about “All molecules which are drugs bind to receptors.” So long as the sentence is punctuated correctly (i.e., without commas), its meaning is unambiguous. No one on earth thinks all molecules are drugs.

Which can be used with restrictive clauses. Jane Austen did so, as did Dickens, Melville, Stoker, and countless good writers. It’s in the King James Bible [“Render unto Caesar the things which are Caesar’s, and unto God the things that are God’s”]. Non-restrictive that appears in Macbeth. Arnold Zwicky has described some of the problems with this “rule”, and there’s a useful history in MWDEU.

The continued popularity of which-hunting probably owes at least in part to the dubious influence of Strunk and White, but not even White himself held to this unhelpful proscription. From Death of a Pig: “…no one took the event lightly and the premature expiration of a pig is, I soon discovered, a departure which the community marks solemnly on its calendar”

In a comment, the blog author David Marsh said that he didn’t use the word rule; that he accepted Austen, Shakespeare and others “broke many of the so-called grammatical rules”; and that it seemed irrational not to follow a “‘useful distinction’ that aids clear and elegant writing”. My second comment, at #52, addresses these points:

It isn’t a question of Shakespeare, Austen et al. breaking so-called rules. Those so-called rules were not there to be broken. The “That Rule” was invented and disseminated later, by prescriptivists who either didn’t know or didn’t care that restrictive which had graced impeccable standard English for centuries. It still does. . . .

Both that and which are commonly and correctly used as restrictive relativizers, though there are subtle differences in how people use them. David, I enjoy your articles (and your tweets), but I don’t think the arbitrary, awkward, and anachronistic “That Rule” does credit to your style guide. You might not have used the word rule, but you might as well have done, given the severity of your last paragraph.

If the distinction “aids clear and elegant writing”, why do great writers persist in ignoring it?

Calling it “arbitrary, awkward, and anachronistic” might have been a bit harsh. (I’m a slave to alliteration.) But the concluding question stands.

There’s also the problem of fronting prepositions: I can’t say *”This is something of that I’ve written before.” I use which, or I strand the preposition — “something I’ve written of” — not that there’s anything wrong with that.

* * *

The Fowler brothers, though they did not invent the restriction, popularized it in The King’s English. H. W. Fowler returned to it in his influential usage dictionary, seeking “clearer differentiation” between that and which and arguing his case at eloquent and extravagant length. Yet he acknowledged that “it would be idle to pretend that it is the practice either of most or of the best writers”.

Consider now the following line from Simple and Direct by Jacques Barzun:

Next is a typical situation which a practiced writer corrects “for style” virtually by reflex action.

What’s funny and instructive is that on the previous page, Barzun had recommended “using that with defining clauses except when stylistic reasons interpose”. This example of immediately self-contradictory which-hunting appears in Joseph M. Williams’s excellent essay The Phenomenology of Error. Williams continues:

after Barzun stated the rule, and almost immediately violated it, no one noticed — not Barzun himself who must certainly have read the manuscript several times, not a colleague to whom he probably gave the manuscript before he sent it to the publisher, not the copy editor who worked over the manuscript, not the proof reader who read the galleys, not Barzun who probably read the galleys after them, apparently not even any-one in the reading public, since that which hasn’t been corrected in any of the subsequent printings.

Another possibility is that people noticed but left it alone. Some years ago, I began collecting literary examples of restrictive which for a blog post showing how common and standard it is — much as I’ve done with comma splices. I soon gave up because the usage is ubiquitous: it would be like collecting examples of semicolons.

A sensible entry in The Columbia Guide to Standard American English says:

most of us use which almost interchangeably with that in restrictive modifiers and rarely but sometimes use that to introduce nonrestrictive modifiers. . . . Best advice: use that or which or nothing, depending on what your ear tells you. Then, when writing for certain publications, know that you may have to replace a good many whiches with thats, and perhaps a that or two with a which, to conform to the “rule” almost no one follows perfectly in other than Edited English and few can follow perfectly even there.

The almost is significant: even those of us who use that and which to some degree interchangeably tend to prefer one or the other in certain ways or with certain kinds of antecedent. There are contextual subtleties, and they have been explored in some depth at Language Log and elsewhere.

Another caveat: heeding your ear is not always a good guide in these cases, because we can habituate ourselves to hear something as “wrong” when it clearly is not. I know I have. Conversely, if we learn that a usage is grammatically and stylistically kosher, our decision to accept it — perhaps despite an instinctual, long-cherished peeve — gradually improves how it sounds to our ears.

And lo: we have more freedom than we had before, and at no significant cost I’m aware of.

If your dialect is an American English one, there’s a fair chance you abide by the “rule”. You’re fully entitled to, just as style guides are entitled to stipulate it for reasons of simplicity or supposed clarity. (Some don’t: The Economist‘s says “Americans tend to be fussy” about making the distinction, but that “good writers of British English are less fastidious”. Hat tip to Lane Greene for that.)

But I don’t think it’s useful or beneficial to outlaw which from restrictive clauses, and I like having a choice of relative pronouns. Let punctuation do the work of clarifying. Used with skill, it does it well.

Postscript: My comments at The Guardian helped convert at least one editor. This morning, I received confirmation of a second. One more, and I’ll call it a trend.

.

Updates:

Arnold Zwicky, following up on this post, laments what may be “a hopeless battle”. He supplies an example of the pseudo-rule being taught to school kids as fact and seemingly being “mangled in transmission”.

Arrant Pedantry explores in greater detail the distinctions between the relative pronouns, and finds that “we do have rules—just not the ones that are proposed and promoted”.

Tom Freeman wonders whether in abandoning the That Rule we would lose a useful distinction. After examining the evidence, he finds there are “any number of ways to rephrase for clarity”, and honourably recants.

Robert Coren, in a comment on Arnold Zwicky’s Google+ page, tells an illuminating tale: “Several decades ago, my workplace had a tech writer who was a serious which-hunter, and she had so terrorized at least of [sic] the developers that he produced a draft that avoided “which” entirely, using “that” even in non-restrictive clauses, resulting in pretty much unreadable, or at least incomprehensible, prose.”

Copyediting.com kindly includes this post in its October 21 news roundup and, interestingly given what I wrote in this comment, italicises which in the title.

Geoffrey Pullum, at Language Log, says that far from helping American users of English, the pseudo-rule “ruins their lives”. He presents and analyses an example that shows how insane one’s prose can become because of confusion over the rule, and describes the Fowler brothers’ proposal as “unmotivated, unimplementable, and stupid”.

Peter at 9 Months with the Chicago Manual of Style agrees with me, noting that the that/which distinction “was never a rule to begin with”, and elaborating on the CMOS‘s “lukewarm” endorsement of our right to choose.

I recently got a copy of the new fifth edition of the American Heritage Dictionary; here are a few lines from its usage note on the matter:

this use of which with restrictive clauses is very common, even in edited prose. Moreover, in some situations which is preferable to that. Which can be especially useful where two or more relative clauses are joined by and or or: It is a philosophy in which ordinary people may find solace and which many have found reason to praise. Which may also be preferable when introducing a restrictive clause modifying a preceding phrase that contains that: We want to assign only that material which will be most helpful.

Arrant Pedantry, in a post examining what corpus data reveal, finds that the distinction is not useful and that “its usefulness is taken to be self-evident, but the evidence of its usefulness is less than compelling”.

In a subsequent post, Arrant Pedantry unpacks the strange behaviour of relative clauses, especially that, and justifiably describes it as “far more complex than most editors or pop grammarians realize”.

Peter Harvey neatly summarises the commas-and-relative-clauses situation and describes the pseudorule as “nonsense”.

Geoffrey Pullum, at Language Log, calls the rule “a time-wasting early-20th-century fetish, a bogeyman rule undeserving of the attention of intelligent grownups”. And he blames me for infecting him with “false optimism about changing people’s minds”. [*evil cackle*]

On Sentence first, “A comma, which muddles meaning” quotes a Guardian editorial with a comma muddle that shows how obeying the rule can undermine communication. The Guardian style guide editors conceded that I may be right (i.e., that they may be wrong). There’s hope yet.

Random Idea English offers a useful overview of the usages and says the rule “has nothing to do with grammar”. A later post on which-hunting points out that “the use (or not) of commas is the main distinguishing feature (apart from context) between defining and non-defining clauses in writing, rather than the use of that or which“.

Mark Liberman at Language Log laments a link at Reddit perpetuating the “phony” rule, and provides a brisk summary of the history of the contentious usage.

Revisiting the topic with a terrific post at Arrant Pedantry, Jonathon Owen shows how the that/which rule, “rather than regularizing the language and making it a little more consistent, actually introduces a rather significant irregularity and inconsistency.”

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71 Responses to That which is restrictive

As I was reading, I thought to myself that I’d always automatically used that and which in ‘the rules’ manner (though I tend to lean towards ‘that’… I think), and then you mentioned the bit about Americans. Maybe it’d because we’re made fun of for our English sometimes and therefore those of us that do happen to care, care a lot? Who knows.

It looks as if you’ve already consulted Huddleston and Pullum on the subject. It is they who seem to have introduced the helpful terms ‘integrated’ and ‘supplementary’. In ‘A Student’s Introduction to English Grammar’, they conclude, in one of their prescriptive grammar notes, ‘Integrated relatives with “which” are grammatical in all varieties of English, and the notion that there is something wrong with them is just an invention of prescriptivists.’

And of course “utterly bollixed” is utter bollocks. The distinction isn’t made in BrE because it never existed either in BrE or in the common ancestor, or indeed in AmE before the date of its invention.

Stan:
I agree with that which you say. In certain constructions which you mention, “which” is the choice; no one would ask “That one do you want?”(Although you would say “Do you want that one?) In conversation, “which” is often the choice for emphasis, as in “The choice which I gave you is the right one.” Although “that” works just as well in the foregoing.In most instances, which and that are totally interchangeable, and for my money, that’s that, unless youu’re asking me which is which. I was underwhelmed by the Guardian column.

I find it odd that Sylvia uses the phrase “why muddy the waters” when surely it’s the prescriptivists who muddy the waters by stirring up the dirt with a rule they’ve invented out of thin air! Letting English take care of itself is the opposite of muddying the waters, to my mind.

Having a choice of words gives the writer more degrees of freedom to craft a better-sounding sentence. Language is not supposed to be mechanistic. Simplicity is not a virtue.

eritta: I too find it curious that the BrE convention is looser on this point. There’s probably a variety of reasons why formal AmE adopted the “rule”, but none are obvious to me.

Barrie: Yes, I consulted Huddleston and Pullum’s Student’s Introduction… and, happily, agreed entirely with the portion you quote. Their terminology is helpful and smart.

Sylvia: Why muddy the waters? This is a question I would put to the prescriptivists. (I see Adrian, aka Dragon, concurs.) It’s not simpler: there was little or no confusion before, and there is a great deal now because many people rely on the “That Rule” instead of trusting to punctuation. It replaces an exemplary and unproblematic option of centuries’ standing with an unkillable zombie non-rule that serves to increase uncertainty, redundancy, and the perception of wrongness where none exists.

John: Quite so. Yet some are evidently determined to make and circulate the distinction.

Marc: They’re often interchangeable in restrictive clauses but much less so in non-restrictive clauses, where that is very unusual. Maybe this asymmetry is part of what leads people to believe in or enforce the “rule”, because they think engineering a language is a straightforward matter. It might have been simpler had the language developed that way, but it didn’t.

Dragon: Agreed. Letting English take care of itself is not something grammaticasters can do, though. They think it needs fixing, finger-wagging, and knocking into more orderly shape. Like an unruly classroom.

Hi Stan. Your post reminded me that Julian Barnes touched on the subject in his preface to ‘Letters from London’. He speaks of his dealings with the style police at The New Yorker, and says:

“My own particular weakness is a refusal to learn the difference between which and that. I know there’s some rule, to do with individuality versus category or something, but I have my own rule, which goes like this (or should it be ‘that goes like this’? – don’t ask me): if you’ve already got a that doing business in the vicinity, use which instead. I don’t think I ever converted the style police to this working principle.”

I would once have been right there alongside him, relying on commas to do their thing, and indeed still am in spirit, but it is difficult to return to the innocence that precedes awareness of a ‘rule’ or guideline.

Mise, just remind yourself this is a rule like “don’t wear two shades of blue together”. Just because somebody pronounces it a rule doesn’t make it one.

Considering that many of the people who proclaim this “rule” also say “don’t end sentences with prepositions”, they find themselves in a box with a restrictive clause introduced by a preposition, as in “the book of which I was speaking last week is now available”. But you never hear “of that”, do you?

Mise: That’s a good illustration of the uncertainty this non-rule has wrought: people (even accomplished writers) sensing that there’s a rule they should be aware of, but not knowing what it is. At least Barnes went his own way. My preference tends to be for that in restrictive clauses, but I use which occasionally, knowing well that it will irritate a subset of sticklers. The problem is theirs.

Ridger: Two shades of blue? Hey, there’s another rule I didn’t know I was breaking! Maybe I’ll mismatch my socks tomorrow in celebration. Your point about prepositions is a good one; I touched on this briefly at the end of the second section but I didn’t elaborate on it; some of the links I’ve included discuss it in detail. It’s worth noting that the Guardian style guide calls the no-preposition-stranding nonsense “a fallacy”.

Great post, Stan. I never thought twice about this until moving to North America and working as a copyeditor and being revised myself. Suddenly lots of whiches were being changed to thats. But today I find myself applying the rule. Not because I agree with it, but because I wonder if it hasn’t become like the words Garner calls “skunked”. I’d hesitate to say which (in a North American text at least) for fear of some reader thinking me illiterate.

[…] so much attention from usage commentators, and I decided I should write a post about them. I was beaten to the punch by Stan Carey, but that’s okay, because I think I’m going to take it in a somewhat different […]

Terrific post; thank you. I’ve been trying to fight his battle for years, mostly with lawyers, who seem to be taught this “rule” and a lot of other nonsense in law school. One thing maybe worth adding is that the argument that we need the distinction to avoid ambiguity is nonsense. Most people have only one relative pronoun–“who”–to use when talking about people (yes, you can use “that” and “which,” but few do), yet we seem to get along without undue confusion there. Any sentence that needs a strict which/that distinction to avoid ambiguity should be rewritten.

Peter: Thank you. What a shame that readers would think you illiterate for using restrictive which. I would encourage you to use it as you see (and know) fit, so far as possible. Make sticklers responsible for their own misinterpretation. It reminds me of a chat I had on Twitter recently. Someone asked me about the validity of till, I said it was fine (and older than until), but he felt it was skunked, and he avoided it because enough people “look at it and pause”. Another perfectly good usage, off limits to some speakers for no good reason.

Alan: You’re welcome; thank you for reading it. Ridger is right: that’s an excellent point about who. The ambiguity argument is, as you say, without much foundation; and in rare cases where it arises, recasting the sentence is probably advisable. As I said of the Guardian‘s borrowed example: So long as the sentence is punctuated correctly (i.e., without commas), its meaning is unambiguous – so long as the reader hasn’t bought into the non-rule, of course.

The Williams paper, “The Phenomenology of Error,” points to “We were all locating error in very different places,” and when we read, we look expressly for those places. The ideal reader recognizes a paper is unmapped territory, but we are not taught to be ideal readers, but to find error, but whose error is it? BTW, Williams loaded his paper with errors, traps for his readers with maps. One must read through to the end to get that. But thanks for this post. The title alone is instructive, and will serve as a useful reminder of that which, with commas, might be correct, or at least not in error.

Joe: Thanks for your comment. Williams revisits some of the essay’s ideas in his book Style: Toward Clarity and Grace. You’re right: we are taught to find error (it’s part of what I do as an editor), so our judgement comes to play a significant role in assessing what an error is, and when and where and why it’s an error.

A common assumption is that a usage is or is not an error, with less common contextual qualifications relating to geographical dialect, degree of formality, and so on. There is also, as Williams writes, “great variation in our emotional investment in defining and condeming [sic] error, great variation in the perceived seriousness of individual errors.”

So the location of an error is greatly distributed, and unevenly so, and our emotional responses to errors can vary widely and change quickly.

In the title, I toyed with putting which in quotation marks, to emphasise the secondary meanings (there are at least two), but decided not to for simplicity’s sake, and because it would undo the main sense. As you say, it can serve as a reminder. I would be delighted if it did.

substuff: All right, let’s call it provisional for now! But I hope that once you’ve comitted to an unimpeachable restrictive which of your own devising, you’ll feel the weight of historical legitimacy nudge you towards a second. Then follows the delight of a successful experiment, and inevitable full conversion.

Ellen: It is possible, though to my mind unlikely, that Barzun knew what he was doing with the which in question. But I’m at a loss as to what “stylistic reasons” might have justified it for him.

WWW: Over the weekend, my sister reminded me that she asked about that/which sometime last year, and I replied: “Can of worms!” I’m glad I finally got around to opening it, and I agree with you: commas play the significant role.

It doesn’t matter if he knew what he was doing. It doesn’t matter if he made a conscious choice; many stylistic choices are made with no conscious thought to alternatives. But I certainly see stylistic reason for “which” there. And only after putting thought to it am I conscious why “which” is better. To me, “that” makes it parse differently.

a typical [situation which a practiced writer corrects…]

vs

a [typical situation] that a practiced writer corrects

That is, it changes whether “typical” modifies “situation which/that…” or “which/that…” modifies “typical situation”. Or rather, it changes which of those two readings comes more naturally for me as a reader.

So, nope, doesn’t break his rule. Does make his rule seem meaningless.

A couple of years ago, I was involved in proofreading a book before it was sent to press. The copy was very clean, but one of the other proofreaders dutifully changed every restrictive “which” to a “that”. And the author apparently never used restrictive that, so there were lots of changes—probably four or five per page.

I think we must update Seoirse Bearnárd Ó Sé’s famous remark in the preface to Pygmalion, and say that is impossible for an anglophone to pick up their keyboard without making some other anglophone hate or despise them. (Some will be hating on me already because of the third person singular indefinite pronoun I’ve just used, though hopefully no one at this blog.) So unless we are not to speak or write at all, this risk must simply be assumed.

Another counter to the ambiguity argument is to point to the case of German (and I believe also Dutch), which sets off both restrictive and non-restrictive clauses with commas, and leaves it up to the listener’s remarkable capacity for understanding to figure out what is meant. Indeed, I cannot think of another language besides English that has a formal way of marking the distinction even in writing. Yet somehow their societies have not collapsed from intolerable ambiguity.

Ellen: Yes, it does make the “rule” seem meaningless. I don’t parse the options as you do, but I agree that it’s about style: that and which are subtly different, and differently different to different people.

Jonathon: Good for you. But what a waste of time for the which-hunting proofreader, who presumably does the same thing with every text.

John: I love that line of Shaw’s, though he said it of Englishmen rather than anglophones; and I think anyone hating on you for singular them will be doubly outraged by the phrase hating on. Maybe the fact that societies have not collapsed from linguistic ambiguity serves to sustain the threat in the minds of doom-mongers. They can keep dangling its apocalyptic potential over themselves and the rest of us rather than engage with the evidence at hand.

[…] usefulness of the rule, but I take it as evidence that it’s just not useful. And anyway, as Stan Carey already noted, it’s the commas that do the real work here, not the relative pronouns. (If you’ve […]

Thanks for the great post. I agree that there is no point in teaching this as a meaningful rule. And I think that removing that/which from the centre of the conversation helps to put punctuation at the centre. Punctuation, if we are to understand and then communicate our meaning, is the key point. As a teacher of writing, rather than an editor, I am interested in making sure students understand the real importance of using punctuation to correctly convey restrictive/non-restrictive status (and, in the most interesting cases, to decide between them). I am certainly doing my best to introduce the supplementary vs. integrated terminology since I think it has an intuitive accuracy lacking in our existing terms. One complicating factor for me is the way (as Williams explains so well) that error is in the eye of the beholder; a scientific editor may genuinely find a restrictive which ambiguous. Not grammatically incorrect but actually ambiguous, as though commas just have been mistakenly omitted and need to be added. So I suggest scientific writers maintain the distinction as a clarifying practice designed to satisfy potential readers (rather than as a rule). Thanks again.

Thanks for your thoughtful comment, Rachael. Punctuation, as you say, is (or should be) central to this issue. I’m encouraged by your use of the supplementary and integrated relative terms in your teaching. I find myself using them more in discussion once they have been identified in relation to the more familiar terms.

[…] post from APA Style. For a more nuanced, historical view, try Stan Carey’s excellent post on this topic (as usual, Carey also provides a very helpful roundup of what others have said about this […]

[…] used with a comma to set off a non-restrictive clause. Normally which does this job. (Which is also fine in restrictive clauses, by the way, despite the pseudo-rule that forbids it. The first link explains the […]

Interestingly enough, I’ve always taught my ESL students that restrictive clauses can use all three options – that,which, or null. I always approached it as an issue of style and formality, but not as grammar. It’s presented that way in all the textbooks I’ve used as well.

It has annoyed me to no end for years when I was “corrected” for using which rather than that. And I’m American! :)

I’ve never really noticed it in the writing of the students at my college – to be honest, there are too many other real issues they have with their writing to notice the that/which distinction! They’re too busy writing things like, “The moment I saw this kid the first thing I thought was that he was the kind of kid who was the type of kid who was a bully, so I never talked to him at first.” But now I’m curious…

limr: Some people just can’t collect enough rules, especially if their first impression is that it simplifies a complex bit of syntax. On closer inspection this one turns out to be spurious and counterproductive, but many people don’t look that closely. It’s a relief to know that textbooks are treating it so sensibly. Let’s hope the pedants and style guides catch up eventually!

[…] There are more serious shortcomings. Comma splices are not always errors, but they oughtn’t to appear in a book on punctuation without comment; this one has a few. It says em and en dashes are “longer than the hyphen (-) which is not a dash”, which implies some hyphens are dashes. This construction recurs. (See my post on that vs. which.) […]

[…] I’ve written before about a comma(,) which muddles meaning, and a comma with restrictive which. The first was in a newspaper editorial, the second in a de Maupassant translation; both were inserted seemingly because of an unfortunate belief in the bogus rule about that and which. […]

First I must confess that I am not a native English speaker, which is not curious at all. Far more strange is the fact that, about a couple of years ago, I realized that certain late-nineteenth or early-twentieth century writers like Conan Doyle or E. M. Forster often used “which” when introducing a restrictive clause. I knew that it was not wrong, but I found it a bit unusual. My question is: Is it for the sake of formality that they avoid the use of “that” with such tenacity (see Sherlock Holmes’ stories, for instance)? I would really like to know your opinion on this subject. Thanks.

That’s a good question, Fernando. I can’t say for sure why any particular author would prefer which to that in restrictive clauses, though I imagine most writers use both. They may choose one over the other in a given context depending on factors such as formality, euphony, and rhythm.

Which is the more formal and somewhat ‘heavier’ option. It may also simply be a writer’s usual preference, for no definite or conscious stylistic reason. But even so, I don’t think many writers avoid restrictive that altogether; they just go with what sounds better, and form habits accordingly.

The presence of another that or which serving a different function in the same sentence can motivate use of the other term; e.g., “Which design is the one ___ you decided on before?”

Hello Stan. Thank you very much for your prompt reply. I find your answer cautious and yet precise, for it does seem really difficult to account for the predominance of “which” in the restrictive clauses employed by a writer.
Notwithstanding that, it is amazing how fond Conan Doyle was of that pronoun. This new rule created by the grammarians from the States should then make clear that it does not apply to the work of the illustrious Scotchman. As a matter of fact, there is a page in “The Boscombe Valley Mystery” in which he disdains the use of “that” in no less than eight occasions.
Let me know begin the transcription.

(1) “ ´There is nothing more deceptive than an obvious fact,’ he [Holmes] answered, laughing. ‘Besides, we may chance to hit upon some other obvious facts which may have been by no means obvious to Mr. Lestrade.’ ”

In this first case, “which” sounds definitely better to my ear. I could not explain why. But in the following sentence there is no reason to avoid the “normal” option, except for the fact that “that” has already been used.

(2) “You know me too well to think that I am boasting when I say that I shall either confirm or destroy his theory by means which he is quite incapable of employing, or even of understanding.”

A few lines later:

(3) [Holmes again] “My dear fellow, I know you well. I know the military neatness which characterizes you.”

The employ of “which” here appears to be a mere whim. But let us go on.

(4) (5) (6) “Therein lies my métier, and it is just possible that it may be of some service in the investigation which lies before us. There are one or two minor points which were brought out in the inquest, and which are worth considering. ”

Having reached this point, the use of “which” reminds me of that word repetition so common in the work of poets and, to a lesser degree, in prose writing.

(7) “This observation of his had the natural effect of removing any traces of doubt which might have remained in the minds of the coroner’s jury.”

This case is different since “that” had been used several times in the previous sentence. But “which” resumes its capricious character in the next instance:

(8) “ ‘On the contrary,’ said Holmes, ‘it is the brightest rift which I can at present see in the clouds.’ “

All in all, I would say that the continuous choice of “which” by some Victorian and Edwardian writers tends to slow down the pace at which we read their books. You have spoken of “which” as “a ‘somewhat’ heavier option”, which makes me think that you might be of the same mind. But is it so?

P.S.: in my previous comment I had written “far more strange”. Should I have not said “far stranger” or are both correct?

It’s not difficult to account for the popularity of which in restrictive clauses. The usage is fully grammatical and has been used in good prose of all sorts for centuries. Both it and that are completely normal in that context, and the instances [which] you find whimsical or capricious seem perfectly ordinary to me.

I find nothing amazing about a writer’s preference for one over the other, and I see no reason to infer “disdain” for the pronoun not chosen.

Far more strange and far stranger are both fine. The second phrase is more common in current writing, but there’s nothing wrong with either.

[…] group of dialects – but we often disagree about what should be regulated and why. The that/which rule, for instance, survives largely through the work of editors who consider it important (I think the rule is unnecessary and counterproductive). […]

[…] for the spread of one of my grammatical bêtes noires, the that/which rule, over which Marsh and I have disagreed before. He still prefers the simple rule, but his position appears to have relaxed: “although that is […]

[…] A note on terminology: non-restrictive relative clauses are also called non-defining or supplementary relatives, distinct from restrictive, defining, or integrated relatives. (There’s more on this and associated “which-hunting” in my oversized that/which grammar post.) […]

[…] clauses is ‘which’, but that’s just me. Other writers about English (eg, Geoffrey Pullum and Stan Carey) have thoroughly discussed the history and current usage of this construction and the varying […]

[…] post from APA Style. For a more nuanced, historical view, try Stan Carey’s excellent post on this topic (as usual, Carey also provides a very helpful roundup of what others have said about this […]

As long as we’re adding to this (excellent) post four years on, Americans may be interested to know that when White wrote “The Elements of Style,” he had to revise the late Prof. Strunk’s prose to replace Strunk’s restrictive relative “which”es with the “that”s White preferred. Strunk & White doesn’t mandate the rule; only White does (except when he breaks it himself).

Thanks, Jan. I thought I had mentioned that, but evidently not. It makes White’s own use of restrictive which (e.g., in ‘Death of a Pig’) all the more striking, given his committed campaign against it.

[…] the last response: No, it really doesn’t. Commas do all the work of disambiguation, as Stan Carey explains. The car which I drive is no more ambiguous than The man who came to dinner. They’re only […]

[…] baseless and a misinterpretation of something Fowler once said. There’s a good post here: That which is restrictive and Arnold Zwicky has gone one further and collated an inventory of postings on the […]

[…] a writer’s personality repels, it will not avail him to eschew split infinitives, to master the difference between ‘that’ and ‘which’, to have Fowler’s Modern English Usage by heart. Soul is more than syntax. If your readers […]